特定健診での慢性腎臓病検出における血清クレアチニン測定の意義

Abstract

A specific screening test system for detection of Metabolic Syndrome was started in April 2008. This test includes urine protein but omits serum creatinine. This test system assumes this position based on the view that health guidance or recommendation of health examination in subjects diagnosed with hypertension or diabetes mellitus will help detect otherwise overlooked renal dysfunction. I conducted an investigation to obtain evidence that the specific screening test system can detect CKD. The investigation was conducted in 931 subjects who had been examined for urine protein, blood pressure, blood glucose, and serum creatinine. This investigation was invested with an aim to determine the frequency of renal dysfunction among the subjects in whom CKD is ruled out in the specific screening test because they test negative for urine protein. Of the 931 subjects, 169 developed a positive test for urine protein. Of 762 subjects testing negative for urine protein, 226 had renal dysfunction with eGFR <60 ml/min/1.73 m2. The urine protein test alone let 57.2% (226/395) of subjects escape the detection of CKD. Of the 226 subjects, 156 had hypertension and/or diabetes mellitus and were found to have renal dysfunction when their serum creatinine concentration was determined. As a result, the rate of CKD overlooking was reduced to 17.7% (70/395), but the sensitivity and specificity of this test system were 69.0% and 43.7%, respectively. It is still insufficient in these respects. The specific screening test system let 226 of 395 subjects (57.2%) escape the detection of CKD. This result suggests that the test system should include the measurement of serum creatinine concentration.